Maximum and Average Urine Flow Rates in Normal Male and Female Populations—the Liverposl Nomograms

Abstract

The study of voiding in men and women has been handicapped by the lack of a normal reference range covering urinary flow rates over a wide range of voided volumes. Normal volunteers (331 males and 249 females) were studied. Each voided once into a calibrated Dantec Urodyn 1000 mictiograph. On a second occasion 282 men and 46 women voided. The maximum and average urine flow rates of the first voids in both sexes were compared with the respective voided volumes. Nomogram charts, in centile form, for both the maximum and average urine flow rates were constructed using statistical transformations of the data. Males showed a significant decline in both urinary flow rates with age, although there was no statistically significant variation in either urine flow rate with respect to first versus repeated voiding. Females showed no statistically significant variation in either urine flow rate with respect to age, parity or first versus repeated voiding. The maximum and average urine flow rates in both sexes showed an equally strong relationship to voided volume. No artificial restriction of voided volume, e.g. minimum 200 ml, appeared appropriate. These nomograms offer reference ranges for both maximum and average urinary flow rates in both sexes covering a wide range of voided volumes (15-600 ml).

Erratum/Apology: Re: Uroflowmetry in healthy women: Development and validation of flow – volume and corrected flow – age nomograms

“…Consistency of repeated measurements has been reported in various studies, including the one by Prof. Haylen et al 14 and us too. 15 Similarly, as nicely depicted by Prof Haylen et al 14 there is remarkable consistency of centile ranking of repeated voids, therefore, negating its importance in construction and validation purpose for nomograms.…”

Voiding dysfunction in men: pathophysiology and risk factors

“…59 To correct for this relationship, some individuals have developed nomograms, but there has not been one that has become universally accepted. [60][61][62][63][64][65][66][67][68] Another weakness of using the maximum flow rate to diagnose BPH is that is tends to have diurnal and day to day variability. 50,69 Most BPH trials tend to use flow rates less than 10-15 ml s À1 as entry criteria.…”

Computerised triage in a prostate assessment clinic

“…When results of the flow studies are entered, the program plots the values on four published nomograms for flow studies -Rollema (Q max and T void ), 6 Susset 7 and Haylen. 8 Three of these are Q max nomograms and one is for voiding time. The nomograms are used to score the flow between 0 (unobstructed) and 2 (obstructed).…”